My 427 SOHC Build..... Finally the time has come!

[cobracammer]

I actually wasn't pulling the vacuum signal.  I was going off the #'s Jay gave me.  Those were already the min the ECU needs.... So when I ported manifold vacuum to the brake booster, its now prob less.  FAST actually suggests not using their system on cars with vacuum assist brakes. 

[WConley]

I actually meant the location the ECU is getting its vacuum signal from.  That should not be anywhere near the booster line.

You want to plumb the ECU vacuum sensor up near the front carb plenum if possible...

[cobracammer]

I think it pulls it from the front most throttle body.  Brake booster is pulling from the back of the manifold. 

[WConley]

Ok - Got it.  You're probably doing about as well as you can with that vacuum signal then. 

I wonder if there is another "hack" available out there to make the system work well with your vacuum level.  Not sure sitting here in this armchair!

[newfalconowner]

i got my Fast efi kit off a guy that tried it, and he had 7in vaccum, so he sold it to me.. I haven't checked to see what my vac. is yet.

I find letting the O2 sensor heat up before starting it helps a lot in getting started for me by using the handheld to let me know, or it wont start right away.

My car has manual disk brakes, so I don't have any vaccum loss like that.

[newfalconowner]

if that new handheld isn't working for you,, might as well send it my way lol

[My427stang]

First, I think I'd put a vacuum gauge on there and see what you can see.  Get some numbers.

Second, advance the initial timing if you have to, and see if you can get the vacuum up (if you need to), then you can adjust total to make up for it.  You have a stout starter, but if not, you could even start it airplane style by hitting your button, then turning on the ignition.

Third, call FAST and see if it is possible to run in open loop at idle.  What this will do is essentially make the TBs an electronic carburetor and not require (or adjust for) any inputs, however, you will have to screw with settings because you lose the "learn" feature for idle when you do that.  Additionally, many of us use open loop for initial tip-in to make up for a bunch of overlap, then after a desired RPM, it goes into closed loop, same at cruise

Fourth, you could add a little valve lash (never did a SOHC, so not sure if it's possible) but it should be feasible, that may bring you a little more vacuum, although that doesn't bring much.

Finally, Jay can say more on what the chance of this is, but if you advanced the cams, you can likely gain significant vacuum at dile, but not sure how easy that is on an aftermarket SOHC

However, in the end I am quite surprised that it would need more vacuum than you have. Somehow, you likely just need to get into the system and tell it what it needs to know.  I know you spent dough on this new handheld, but you possibly could be getting into the realm of laptop tuning.  That's why I like a laptop so much better, I can long, tweak, sit at my computer think about it, try something and basically hit undo and redo 50 times a day if I wanted to

ON EDIT: I spent a very short time with the EZ-EFI instructions, and some questions

1 - Are you using it to control the ignition?
2 - There is quite a bit of tuning capability, but moreover, there is a ton of calibration capability.  TPS, IAC, etc, Have you done all of those?  We know you know of the TPS, but I saw a page that calibrated the IAC and throttle plates, that triggered my question.
3 - Just to clarify, do you think that your brake booster is bleeding vacuum when sitting there at cold start?  It shouldn't

Get a vacuum gauge on there, see what it says, this may be a moot point.  However, if it's only slightly low, adding a little initial and adjusting back to total may put your mind at ease.

[cobracammer]

OK, went out today with a thought......  It cant be an issue with vacuum as it runs near perfect once it reaches operating temperature and the "AL" or adaptive learning kicks on!  It has to be something with the engine being cold.  So I started it, it started right up...  started the same rough idle at like 500-600 RPM, so I kept on the throttle for a few minutes just to get the temp up (kept it around 1000 rpm's).  Once I got up around 140 degrees, the AL feature turned on and the car idled at the 1000 rpm.  I wanted to take a video of each screen at idle, and also revving the engine.  I am not sure what I am looking for exactly, but I figured people more familiar with EFI's would see something (possible).  I was curious about "LOAD% " on the last screen.  is that supposed to hit the 90's when the throttle is pushed?

 Just to rehash....

Fuel pressure at the regulator is 43 PSI (without vacuum reference).  With the vacuum reference connected and the engine running, the gauge on the regulator shows about 40 PSI.

Dual Quad set-up so 8 fuel injectors

Accel Fuel set to -3 (this was due to rough acceleration in 1st and 2nd gear).  Putting to -3 smoothed it out.

RPM's at idle set to be 1000 RPM

I was told by the fast tech that ideally we are looking for 15-20 on the IAC at idle

still smells a little rich at idle..... especially during its warm up when idle wants to fall below 500 RPM and stall without me keeping on the throttle a little to get the engine warmed up (?)

 https://youtu.be/s_IpoCkkgNs

[My427stang]

So, I read all over the net with other complaints, then dug through some of the instruction sheets.

I do not see a fast idle option, only an enrichment option for cold start.  If it does not have one, that's a real pain in the ass to put it lightly.

Could you send a link to instruction for the programmer you are using?  My hunch is, you got what you got if there isn't a cold start idle speed setting

I will say, you might be able to trick it a little by opening the throttle blades and recalibrating the TPS, then it "might" give a little more air when cold and the cold enrichment might help, but that's a pretty cheesy setup if you as me if it doesn't use the IAC as intended when cold

BTW, I see nothing crazy, would have to see how load is defined to give an opinion, but IAC looks good enough to me, if you want the number lower, open the throttles more, the IAC will open less as a result. 

[My427stang]

BTW I found this regarding your LOAD question

LOAD%   Calculated load.  A comparison of the current manifold pressure vs. the ambient atmospheric  pressure.    Unlike  the  reading  from  the  MAP  sensor  –  which  is  affected  by  altitude  –  Load  should  always   be  consistent.    That  is,  wide  open  throttle  should  ways  be  around  100%   regardless  of  altitude  and  ambient atmospheric pressure.

I figured it was a vacuum reading, that won't tell you much until you have a load against the engine.

As far as the IAC, I think you are about there.  It's idling well at temp and the instructions say "It’s range is from 5 to 180.  Generally, this will be around 20 idling out of gear with a fully warmed up engine."

I am amazed they didn't add a field for an additive RPM when cold.  (ie 250 rpm when below 140)  Every thing I have tuned has had something like that.  They already have the ability to do that because if I understand it correctly, it has an input for A/C that when energized raises the idle slightly.  Amazing they didn't put a cold fast idle setting in

[cobracammer]

Hi Ross.  Thanks.  Yea, no such luck.  They have other models ( XFI and Sportsman) which I think are a lot more configurable.  EZ efi doesnt have many options.  The new handheld should give me a few more options, but i think its just adding and pulling fuel. Not adding rpm's at cold start ( unfortunately).

I guess its good for now  lol

[My427stang]

Something I read in the instructions was that it "raised the a little bit when cold"

I don't know how much, but it's odd that yours is lowering the idle when cold.

Are you controlling timing with the FAST setup?

[cobracammer]

Something I read in the instructions was that it "raised the a little bit when cold"

I don't know how much, but it's odd that yours is lowering the idle when cold.

Are you controlling timing with the FAST setup?

Hey Ross.  No the EZ version (which I have) does not allow for control of timing.  :0(

[newfalconowner]

wander if you can use a carb idle solenoid thingy and wire it to the a/c part of the ecu?

[cobracammer]

OK guys.  Not a good day.

Got back from another drive as I am trying to give the EFI computer time and inputs to learn.  Going up through the gears, down shifting, Quick acceleration, Cruising in gear, etc.  On my way back home, I heard a "whizzing noise" from the transmission.  It was only there when the car was in gear, and went away when the clutch was depressed.  So I decided to go very slowly home and see what  this new issue was.

Car back in the garage and back up on Jack stands....  First issue is another puddle of oil under the car.  So this time, with flashlight in hand, started the search.

The bottom of the oil pan had a coating, as well as a drop or 2 on the scatter shield.  There was oil residue on 2 or 3 of the Main cross bolts as well as on the oil filter adapter (which I was going to tighten up a little on the first oil change as you can not access the bolts with the filter attached.

Shined the light up on the back of the heads as well as the back of the block and couldn't see anything (from what I could see).  not dripping from one place as much as it seemed to be "spraying" for lack of a better word, which makes it had to track down unless the car is running and I am under it with the light?  Wiped it all back down as well as tightened the oil plugs on the pan.  Will have to figure this out while its running.

Second and most pressing issue was not the "whizzing" noise coming from the transmission.  With the light shining into the bell housing, the throw out bearing seemed to be in good shape and seemed to be right where it should be (just touching the tips of the pressure plate fingers (just touching).  I was able to put my fingers in there and turn the bearing freely so I know its not pressing against the fingers when the clutch is not being pressed....

Then I saw it (and luckily I made it home without breaking anything).  There is a locator stud that screws into the spacer plate on the transmission.  This is the stud that locates the throw out bearing and keeps it from spinning.  Somehow, it started to unscrew!  and the tip of it was just starting to contact the fingers when the car was in gear.  When I pressed the clutch, the fingers got pressed in and then the stud no longer made contact .  This is why the whizzing noise went away when I pressed the clutch.  I (for the life of me) don't know how it started to unscrew, but it would now seem that the transmission needs to come back off so I can screw it back down and see if I cant wire it somehow to prevent it from coming lose again?

Either way, I huge pain, but luckily caught in time.

As for the oil leak(s), my hope is that it is something very minor that you can not see unless the system is under pressure. Tightening the valve covers seemed to stop the leak for a day (but I was just checking it at just idling in the driveway and not with the oil pressure very high)  I am not sure......


Its right about now I wish I had a car lift  LOL.